I. Field of the Invention
This invention relates generally to a hot air gun and, more specifically, to a gas hot air gun that offers smaller physical size for users to carry around, complete burn of gas to reduce carbon monoxide and faster cooling down the whole set after application to prevent users from danger of burning, with a safety switch stopping power or gas flow under some pre-set conditions for safety purposes.
II. Description of the Prior Art
Heretofore, it is known that the “Internal structure of a hot air gun” of Taiwan Patent No. 286505 comprises a main body 1, a handle 2 and a power supply 3. The main body 1 connects to the handle 2 with a hinge 11. The main body further comprises a motor 14, a fan 15 on the motor axis 141 of the motor 14, and a fan blade 16 on the front of the fan 15. A burning chamber 161 is beneath the fan blade 16. An ignition tube 17 interlinks to the burning chamber 161. A temperature control switch 18 and a control rod 19 are installed inside the ignition tube 17. A power supply 3 and gas can are inside the handle 2. A flow control knob 23 is on top of the handle 2. A flame nozzle 24 is on the front of the flow control knob 23. The flame nozzle 24 is ignited inside the burning chamber 161 beneath the fan blade 16. A press button 25 and a switch 26 are installed on the handle to ignite the gas and turn the motor 14 on.
Many drawbacks exist on the known gas hot air gun. The flame burns the gas in the burning chamber 161 beneath the fan blade 16 after the gas is ignited, and hot air is blown out by the fan blade 16 of the fan 15. However, the flame inside the burning chamber 161 is blown out easily and burn users, and thus is not very safe. The temperature control switch 18 reduces the gas quantity after the temperature is high, and when the temperature is low, the gas quantity is increased to have a larger flame. However, such design introduces incomplete burning of gas so that the air injected might contain large quantity of carbon monoxide. Thus, it is very dangerous for users to apply the equipment in a sealed environment.